Label applicators apply labels to articles as the articles are conveyed past the label applicator. Typically, the labels are releasably adhered, in a single column, to an elongated backing strip. The label applicator removes one of the labels from the backing strip and releasably retains it at a labelling station. As the article to be labelled nears the removed label, it is applied to the article. Label applicators of this type are shown, for example, in U.S. Pat. Nos. 3,093,528 and 3,729,362.
Label applicators of this type, while satisfactory for many applications, can introduce delay into as assembly or packaging operation in which labelling must be carried out. For example, the backing strip with the labels thereon is customarily provided on a supply reel. During use of the label applicator, the backing strip is moved from the supply reel to take-up reel. Periodically, the supply of labels on the supply reel becomes exhausted whereupon the empty supply reel and the full take-up reel must be replaced with new reels. The frequency of this change, as well as the amount of downtime, will vary depending upon numerous circumstances. However, by way of example, the reels may have to be changed at 50 minute intervals with approximately 4 minutes of downtime required to accomplish the change. Thus, reel changes may account for approximately an 8 percent loss in production time.
Label indexing or advance; i.e., the removal of a label from the backing strip and applying it to suitable retaining means, is relatively slow while the transfer of a retained label to the article can be rapidly carried out. Label indexing can be sufficiently slow so that the labelling function is caused to be the slowest operation on the production line.
It is known to use a wide backing strip and to provide two side-by-side columns of labels on the backing strip. In this event, two labels are simultaneously removed and releasably retained at the labelling station. The two labels are simultaneously transferred from the retaining means to either the same or different articles. If the labels are transferred to the same article, the downtime problems and slow indexing problems discussed above are not solved.
In order that this prior art construction can be used to apply the labels to different articles, it is necessary that article spacing bear a predetermined relationship to label spacing on the retaining means so that the articles and the labels are properly relatively positioned. This problem is so significant that this arrangement is basically unsuited for most label application jobs. To illustrate, if article spacing or article size are large compared to the labels, the width of the backing strip would have to be greatly enlarged so that the labels would be correspondingly widely spaced on the retaining means. This would result in a great waste of paper in a substantial increase in the size of the supply and take-up reels and the associated apparatus to such an extent that any time saved is not worth the cost involved to obtain it.